Comparing the frequency-lag spectra of AGNs Mrk 110 and Ark 120

The soft excess often seen in the X-ray spectra of AGNs < 2 keV is very complex to model and its exact nature is vaguely understood. Both reflection and warm Comptonization models provide reasonable explanations for the observed soft excess but still ambiguity persists. Here we study the frequency-lag and energy-lag spectra observed at different X-ray fluxes of the AGN sources Mrk 110 and Ark 120. Both sources have a SMBH of mass ~ 108 Msun . We are comparing the high and low flux state’s lag spectra for both AGNs. This study aims to constrain the difference of soft lags (if any) and attempts to associate the spectro-temporal properties with the inner accretion disk among the AGNs.